> The purpose is to get 24p capability to the market a lot quicker,
>which is a good thing. Apparently the writing speed of the current HDCam
>design can handle the segmented frame approach, whereas a continuous write
>of progressive 1080 frames will require a redesign of the machine.
Hi Mike,
If one goes by the claimed 7:1 compression scheme of HDCam, it doesn't even
have the bandwidth to handle good old ITU 601 digital video (270 MB/s as
opposed to 214.3 MB/s). So while there is no reason why a segmented frame
should look any different to a VTR than a video field, the other big charm
to progressive scanning (apart from getting rid of interlace "shimmer" and
"glitter") is improved vertical resolution, and I don't see where that is
being addressed. The bandwidth required by any TV system is the product of
the horizontal and vertical resolutions together, so if bandwidth is
limited, you can't increase one without decreasing the other. My guess is
that the extra vertical detail simply gets lost in the compression, but
that's only a guess since I haven't seen any actual equipment or
specifications yet.
That leaves us with a system that will probably be excellent for "single
strand" 24 fps HDTV telecine transfers that will be downconverted to PAL,
NTSC, and SD. Possibly even HDTV broadcasting. But would it be ideal for
video-to-film, compositing, or archiving? I wonder.
> I'm quite sure Sony and whoever else chooses to participate will
>make an all new format for progressive 1080 recording in the future. This
>is, in fact, their stated intent. I'm also sure that they will, within the
>next 24 months or so, also introduce a 1500 or so line format, a 2K format,
>and probably a 2.5 or 3K format. This is the nature of electronic
>imaging...... obsoleting "standards" within a very short time frame. It's
>also why I value film so highly. And why I question anyone who's buying
into
>the idea that currently proposed HD formats will be with us for any
extended
>length of time.
Or they may decide that sF is all the industry is going to get until their
investment in HDCam is paid off!
While I certainly agree that a true 1080/24P format would be desirable, and
I'd like to see higher resolutions addressed as well, I do not share your
optimism about the industry absorbing an infinite number of video, data, or
formats, or standards for that matter. The laws of economics still apply,
even in the digital age! Surely you recall all the ballyhoo about trying to
support the ATTC's six recommended video formats, which grew into the ATSC's
36 permutations by the time all was said and done. For a while, it looked
like three of them would actually get off the ground, but now the pundits in
some recent trade publications are predicting the imminent demise of 720P,
leaving us with only one standard def format and one high def format to
contend with.
Best regards,
Christopher Bacon
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